Scanguage II settings and accuracy...

[Jack Frost]

Originally Posted by 2004PlatinumTDiSport

I reset mine and it seems to work ok.. however when I stop at a light I am still getting the "9999LHK" message and my average increases.. Anyone else have this issue?
Once I start driving again the average goes back to where it should be..

Thanks

The reason this happens is because you have your Scanguage displaying in metric. The mileage is been displayed as liters/100 km - not miles per gallon.

When you are stopped and idling, your are travelling 0 (zero) kilometers. It is not possible to calculate liters/100 km so the Scanguage displays a nonsense number until you start moving again. For example, try dividing any number by zero in your calculater - what do you get - something like ERR!

It is not a problem, but if you change your setup to display miles per gallon, you won't see 9999 anymore.

[2004PlatinumTDiSport]

Originally Posted by FlyTDI Guy

Uhhh, that makes no sense. My experience has been that idling is way more detrimental to my avg. mileage than I ever gave it credit for. I drive the same 35 mile route to work every day. A stop at the convenience store (5 min) and leaving the car idling will drop my avg. trip by 2-3 mpg vs not. Same if I warm the car up first. How can using fuel and going nowhere increase your mileage?

Actually, that made sense to me.. Because when you think about it.. the car isn't moving and it is using fuel, hence the LHK would increase.. because you're not moving.. but still using fuel..

But I'm still not convinced my SGII is working correctly..

[Jack Frost]

Yes, you are right the engine is using fuel when it is stopped and running, but the metric way of calcuating mileage "Liters/(100 * km)" puts the distance factor in the denominater of the equation. When the car is not moving, the denominater of the equation "100 * km" turns into zero and you cannot divide any number (even zero) by zero.

If you don't believe me, try hand calcuate it. Let us say that your car stops at a red light for 1 minute. Your car in drive will use about one third of a gallon of fuel per hour or 1/60 or .0167 gallons of fuel during that time.

So hand calcuating using the metric way of calculater mileage, we plug in the values; the numerater of the equation is .0167, the denominater of the equation is 100 times zero or zero. Try typing in .0167 into your hand calucater and then divide by zero. What do you get?

There is nothing wrong with scanguage. The problem is the way that metric mileage is expessed. It is an upside down way of expressing the mileage. It expressed mileage as a expression of distance rather than fuel consumed.

Another way of looking at it is that the more efficient an engine, the metric mileage decreases. But with imperial mileage (miles per gallon), the mileage increases. But it is the same engine !!!!

[Kingcodez]

Do you guys update the fill on the SG every time you put fuel in?
I stopped filling the tank because I can seem to feel slight weight changes in the car. Less than half + me and it is great; full tank and it seems sluggish by comparison. Same with when my 115lb wife hops in, I can feel a difference.

Mine wasn't always accurate when guessing how much fuel I put in, but on the first tank it seemed accurate enough, so I just left it alone. When I hand calculate mileage it is very close to what the SG says. I'm just impressed that I can get 55MPG doing 70-80 on the Interstate even with a Beetle. However I'm sure that is due to the wind tunnel effect. Same MPG driving 60-65 on an empty highway. On regular roads I get 55 MPG going 55. I guess the wind tunnel effect really helps a ton. I was getting 50-55 driving from Tampa-Orlando with 4 adults going 80 with sprints up to 90 and 100. No ill effects on MPG. I was bumper to bumper with four other cars though.

City is another story.

[Jack Frost]

I don't update my SG on every fill up. Just get it close enough to your hand calculated mileage and leave it alone.

Absolute and perfectly accurate results are nice, but it is nicer to have comparitive results. If you keep changing your SG everytime you fill up, then how do you know if the mileage that your are getting now has improved because of the last tank of fuel or because you just recalibrated it.

It is better to have the SG left alone once it has been calibrated.

[cleaver]

Originally Posted by FlyTDI Guy

Uhhh, that makes no sense. My experience has been that idling is way more detrimental to my avg. mileage than I ever gave it credit for. I drive the same 35 mile route to work every day. A stop at the convenience store (5 min) and leaving the car idling will drop my avg. trip by 2-3 mpg vs not. Same if I warm the car up first. How can using fuel and going nowhere increase your mileage?

Just to argue my point, the person talking about 9999 is using the metric system and when you are stopped your fuel efficiency number goes up and your mileage goes down. (L/100km vs mpg).

My car always reports 9999 when I am stopped because for me to go 100km at my current speed (which is 0km/h), it would take me 9999L (the max number shown by the scanguage). Technical is should be the infinity symbol, but not many cars/devices can show this so they use the largest number possible.

[FlyTDI Guy]

I suspect we're talking apples and oranges a little bit. If you are referring to real-time mileage, then I understand completely. I never look at that but always AVG mileage. Even stopped, it retains and shows your average for that trip or "session".

If in real-time, then I can see why it would be some weird number. I thought I was clear in my previous post about AVG but maybe not. On the other hand, as it was never mentioned, I ASSumed we were talking AVG, my bad. So are you talking AVG or real-time mileage?

[Vnavone]

Hi All,I just installed a ScanGauge 2 on my 2013 Jetta Sportwagen TDI, and I can't seem to get any reading from the TPS gauge. All the other gauges work fine, but this one is blank. I really want to see this data so I can program my fuel cutoff setting correctly. Am i missing something obvious? Has anyone else run into this issue? Thanks for any help!

[Vnavone]

Originally Posted by Vnavone

Hi All,I just installed a ScanGauge 2 on my 2013 Jetta Sportwagen TDI, and I can't seem to get any reading from the TPS gauge. All the other gauges work fine, but this one is blank. I really want to see this data so I can program my fuel cutoff setting correctly. Am i missing something obvious? Has anyone else run into this issue? Thanks for any help!

I called ScanGauge customer support and they said that some cars don't report TPS to the OBDI. It seems strange to me that this would be the case with my Jetta Sportwagen, since so many other users here are getting TPS readings. Are there any other 2013 Sportwagen drivers here who are getting TPS readings from the ScanGauge 2?